K is for... Kamelion

Kamelion was a bipedal robot which the Master found on the planet Xeriphas. It had been left behind by some early invaders of the planet. Kamelion was so named as it could take on the form of anyone willed upon it by its controller. The Master decided to use it to undermine various galactic centres, and used medieval England as a testing ground. The robot was made to impersonate King John in 1314, in an attempt to stop Magna Carta being produced. The Master believed that undermining parliamentary democracy in England would have a negative impact across all of Earth's history - though the Doctor thought otherwise.

The Doctor fought a mental duel with the Master for control over the robot, which the Doctor won after making Kamelion look like his companion Tegan.

Kamelion thus joined the TARDIS crew, but spent all of its short time on board exploring the ship and its systems.

A psychic link with the Master remained, however. When he was involved in an incident with his Tissue Compression Eliminator, the robot felt his pain from a great distance. The Master re-established control over Kamelion, making it guide the TARDIS to the planet Sarn where he was trapped and requiring help.

A young woman named Peri had been brought aboard the TARDIS by Turlough, and her strength of mind was able to make Kamelion take on the form of her step-father Howard. The Master was able to over-ride this and make it look like himself, but the Howard version sometimes slipped through, albeit with silver skin. 

The Doctor was forced to disable Kamelion with a form of electronic heart attack, to prevent it helping the Master destroy the local community. The robot reasserted its own personality momentarily and pleaded with him to destroy it - arguing that it would always be prone to being taken over and used for evil purposes.

The Doctor accepted this and shot it with the Master's TCE weapon.

Voiced by: Gerald Flood. Appearances: The King's Demons (1983), Planet of Fire (1984).

• A third appearance by Kamelion was recorded for The Awakening in 1984, but cut from the finished programme. It features as an extra on the DVD.
• Producer JNT was keen to have a real robot feature in the programme, and so was interested when approached about one which had been created for advertising. Script Editor Eric Saward and star Peter Davison were not convinced. Unfortunately, once they were committed to using the robot, its programmer, Mike Power, died in an accident. No-one could replace him so no-one could make it work properly. Taking far too long to do even basic movements in studio, it was quickly ignored until a story was prepared in which it could be written out of the series.
• They missed a tick, however, as they could easily have simply employed actors to play the robot in humanoid guise.